Perhaps I misunderstand how you are defining failure here... what would be the failure mode? Perhaps if you could provide an example of the ill-effects that could be seen as a result of this behavior it would clarify the issue?
v/r, Russell On Wed, Mar 6, 2013 at 2:15 PM, N.M. Maclaren <n...@cam.ac.uk> wrote: > On Mar 6 2013, Russell Brennan wrote: >>> >>> >>> Ouch. >>> >>> This seems to be at odds with C's unions, where it is not allowed to do >>> type punning. >> >> >> As of gcc 4.4.6, the description above seems to match the C behavior: > > > Er, no. One simple test does not prove that it will always work; this > sort of thing is most likely to fail because it interacts in very nasty > ways with optimisation. C99 introduced a horribly ill-defined concept > called "effective types", which specifically allows type-dependent > optimisations. I have no idea whether gcc uses it at present, but it > might well do so in the future. > > Regards, > Nick Maclaren. > >
